This application is based on and incorporates herein by reference Japanese Patent Application No. 2000-193099.
The present invention relates to an alternating current (a.c.) generator, which is mounted on passenger cars, trucks or the like.
In one a.c. generator disclosed in JP-A-9-107654, an insulating busing is fit on an output terminal, which is connected to a storage battery via an electric cable. The top end of the cable is sandwiched between a pair of nuts. One nut tightens the bushing and the other nut presses the top end of the cable to the tightening nut. According to this construction, the nut tends to loosen when the bushing contracts during use.
In another a.c. generator disclosed in JP-A-4-165949, a part of a positive-side heat sink (heat radiation fin) of a rectifier circuit unit is extended along an output terminal, which is connected to a storage battery via an electric cable. A nut is fit on the output terminal so that the top end of the cable is held in contact with the extended part of the heat sink. A resin bushing is fit on the extended part. According to this construction, the heat sink must be shaped in a complicated form and the bushing must be sized large. Further, the bushing tends to dislocate, because the nut does not tighten the bushing.
It is therefore an object of the present invention to provide an a.c. generator, which is simple in construction and restricts loosening of a nut.
According to the present invention, an a.c. generator has a rectifier circuit unit and an output terminal unit for connecting the rectifier circuit unit to a storage battery through an electric cable. A rear cover covers the rectifier circuit unit. The output terminal unit extends outward through a fitting hole of the rear cover. An insulating member is fit between the fitting hole and the output terminal unit. A tightening member is engaged with the output terminal unit to tightly fix the electric cable to the output terminal unit. The output terminal unit has a seat surface formed outside the rear cover and the insulating member in a longitudinal direction of the output terminal unit and a threaded part formed near the seat surface. The tightening member is engaged with the threaded part of the output terminal unit to tightly fix the electric cable to the seat surface.
Preferably, the output terminal unit includes an output terminal formed with the threaded part and a first nut engaged with the threaded part to fix the output terminal to the rectifier circuit unit. The first nut has an axial end surface, which provides the seat surface for the electric cable. The tightening member includes a second nut engaged with the threaded part sandwiching the electric cable to the first nut. The axial length of the first nut is longer than that of the insulating member. The fitting hole is shaped to restrict the insulating member from turning.